Rail junction assembly

ABSTRACT

A rail junction assembly ( 10 ) for directing first and second rail vehicle wheels ( 42, 44 ) of a wheel arrangement ( 40 ) is disclosed. The rail junction assembly comprises first and second main rails ( 12, 14 ) and first and second switch rails ( 16, 18 ). A first flange receiving passage ( 17 ) is defined between the first switch rail and the first main rail. A second flange receiving passage ( 19 ) is defined between the second switch rail and the second main rail. The first flange receiving passage is configured to receive a flange ( 48 ) of the first wheel, and the second flange receiving passage is configured to receive a flange ( 48 ) of the second wheel. A wheel control arrangement ( 30 ) controls the first wheel on the first main rail when the second flange is received in the second flange receiving passage, and controls the second wheel on with the second main rail when the first flange is received in the first flange receiving passage.

TECHNICAL FIELD

This invention relates to rail junction assemblies. This inventionrelates to methods of directing first and second rail vehicle wheels.This invention also relates to wheel urging members for use with railjunction assemblies. This invention relates to rail switchingarrangements. More particularly, but not exclusively, this inventionrelates to rail junction assemblies having two fixed main rails and twofixed switch rails.

BACKGROUND ART

Rail junctions, such as found on railway lines, typically comprise twocontinuous rails and two switch rails. The switch rails terminate at thejunction. A change in direction of a rail mounted vehicle, such as atrain, is effected by moving the two switch rails, such that one railengages the continuous rail of the non-required direction, and the otherswitch rail moves away from engagement with the continuous rail of therequired direction.

An alternative method of directing a rail vehicle uses switch railsfixed in position such that passages are defined of just sufficient sizeto permit the wheel flanges to pass on either of the switch rails. Withthis arrangement, the rail vehicle is directed not by movement of theswitch rails, but by the provision of a force on the inner face of thewheel of the rail vehicle, namely the face nearest the centre line. Anexample of such a system is disclosed in WO00/75429. The wheels areconnected to each other by solid axles and, therefore, the distancebetween the inner faces of the wheels remains constant.

The geometry of the passage between the continuous rails and the switchrails is critical, and the support of the rail vehicle depends on therail head widths, rail wear, wheel widths, wheel wear, head stabilityand the required minimum vertical load bearing contact area between railand wheel. The possibility exists that excessive wear on the rail andwheel flange could cause a wheel to have insufficient contact with thesupporting rail.

DISCLOSURE OF INVENTION

According to one aspect of this invention, there is provided a railjunction assembly for directing first and second rail vehicle wheels ofa wheel arrangement, the rail junction assembly comprising: first andsecond main rails and first and second switch rails; a first flangereceiving passage defined between the first switch rail and the firstmain rail, and a second flange receiving passage defined between thesecond switch rail and the second main rail; the first flange receivingpassage being configured to receive a flange of the first wheel, and thesecond flange receiving passage being configured to receive a flange ofthe second wheel; and a wheel control arrangement for controlling thefirst wheel on the first main rail when the second flange is received inthe second flange receiving passage, and for controlling the secondwheel on with the second main rail when the first flange is received inthe first flange receiving passage.

According to another aspect of this invention, there is provided a railjunction assembly for directing first and second rail vehicle wheels ofa wheel arrangement, the first and second wheels having respective firstand second flanges, the rail junction assembly comprising: first andsecond main rails; first and second switch rails; a first flangereceiving passage being defined between the first switch rail and thefirst main rail, and a second flange receiving passage being definedbetween the second switch rail and the second main rail, wherein thefirst flange receiving passage is configured to receive the firstflange, and the second flange receiving passage is configured to receivethe second flange; and a wheel control arrangement for controlling thefirst wheel on the first main rail and on the first switch rail when thesecond flange is received in the second flange receiving passage, andfor controlling the second wheel on with the second main rail and on thesecond switch rail when the first flange is received in the first flangereceiving passage.

According to another aspect of this invention, there is provided a railjunction assembly for directing first and second rail vehicle wheels ofa wheel arrangement, the first and second wheels having respective firstand second flanges, the rail junction assembly comprising: first andsecond main rails; first and second switch rails; a first flangereceiving passage being defined between the first switch rail and thefirst main rail, and a second flange receiving passage being definedbetween the second switch rail and the second main rail, wherein thefirst flange receiving passage is configured to receive the firstflange, and the second flange receiving passage is configured to receivethe second flange; and wheel directing arrangement for controlling thefirst wheel on the first main rail and on the first switch rail when thesecond flange is received in the second flange receiving passage, andfor controlling the second wheel on with the second main rail and on thesecond switch rail when the first flange is received in the first flangereceiving passage.

In the embodiments described herein, the provision of the wheeldirecting arrangement advantageously has the effect of ensuring that thebearing areas provided to the first wheel by the first main and switchrails or by a combination of the first main rail and the first switchrail, and between the second wheel and the second main and switch railsor by a combination of the second main rail and the second switch rail,are sufficient to provide the necessary support to the first and secondwheels even where the rails and/or the wheels are worn.

The rail junction assembly may be a facing only rail junction assembly,in which the first and second main rails diverge from each other in thedirection of travel of the rail vehicle, a trailing only rail junctionassembly in which the first and second main rails converge towards eachother in the direction of travel of the rail vehicle, or a junctionassembly through which the rail vehicle can travel in both directions.

According to another aspect of this invention, there is provided amethod of directing first and second rail vehicle wheels havingrespective first and second flanges, comprising: providing first andsecond main rails, and first and second switch rails, the first switchrail being spaced from the first main rail to define a first flangereceiving passage therebetween, and the second switch rail being spacedfrom the second main rail to define a second flange receiving passagetherebetween; providing a wheel control arrangement, and, with the wheelcontrol arrangement, controlling the first wheel on the first main railand on the first switch rail when the second flange is received in thesecond flange receiving passage, and controlling the second wheel on thesecond main rail and on the second switch rail when the first flange isreceived in the first flange receiving passage.

According to another aspect of this invention, there is provided amethod of directing first and second rail vehicle wheels havingrespective first and second flanges, comprising: providing first andsecond main rails, and first and second switch rails, the first switchrail being spaced from the first main rail to define a first flangereceiving passage therebetween, and the second switch rail being spacedfrom the second main rail to define a second flange receiving passagetherebetween; providing a wheel directing arrangement, and, with thewheel directing arrangement, controlling the first wheel on the firstmain rail and on the first switch rail when the second flange isreceived in the second flange receiving passage, and controlling thesecond wheel on the second main rail and on the second switch rail whenthe first flange is received in the first flange receiving passage.

In the use of the embodiments described herein, the first wheel maytransfer between the first main rail and the first switch rail when thesecond flange is received in the second flange receiving passage, andthe second wheel may transfer between the second main rail and thesecond switch rail when the first flange is received in the first flangereceiving passage.

The wheel directing arrangement may control the first wheel when thefirst wheel transfers between the first main rail and the first switchrail. The wheel directing arrangement may control the second wheel whenthe second wheel transfers between the second main rail and the secondswitch rail.

The controlling of the first wheel on the first main rail and on thefirst switch rail may comprise controlling the first wheel during saidtransfer of the first wheel between the first main rail and the firstswitch rail. The controlling of the second wheel on the second main railand on the second switch rail may comprise controlling the second wheelduring said transfer of the second wheel between the second main railand the second switch rail.

The rail junction assembly and the method of directing a first andsecond rail vehicle wheels described and claimed herein are particularlysuitable for use with any rail mounted vehicle, including locomotives,maintenance equipment, passenger or freight vehicles, as well as for usein any other type of rail system, for example trams, toys, models,metro, light rails or main line rails of any size or type.

The first switch rail may have a first terminating region adjacent thefirst main rail. The first switch rail and the first main rail maydefine a first transition region. The first transition region maycomprise a region of the first main rail and a region extending from thepoint at which the first rail vehicle wheel begins to move laterallyaway from the first main rail to be supported by the first switch rail.The first transition region may terminate at the point at which the railvehicle wheel is fully supported by the first switch rail.

The second switch rail may have a second terminating region adjacent thesecond main rail. The second switch rail and the second main rail maydefine a second transition region. The second transition region maycomprise a region of the second main rail and a region extending fromthe point at which the second rail vehicle wheel begins to movelaterally away from the second main rail to be supported by the secondswitch rail. The second transition region may terminate at the point atwhich the rail vehicle wheel is fully supported by the second switchrail.

The wheel directing arrangement may guide the flange of the first wheelof the wheel arrangement into, or out of, the first flange receivingpassage, and may guide the flange of a second wheel of the wheelarrangement into, or out of, the second flange receiving passage. Thewheel directing arrangement may guide the flange of the first wheel atleast partially through the first flange receiving passage. The wheeldirecting arrangement may guide the flange of the second wheel at leastpartially through the second flange receiving passage.

In the embodiments described herein, in which the rail junction assemblycomprises a facing rail junction assembly or a junction assembly throughwhich the rail vehicle can travel in both directions, the provision ofthe guide arrangement is advantageous.

The guiding of the flange of the first wheel into, or out of, the firstflange receiving passage may comprise guiding the second wheel duringthe transfer between the second main rail and the second switch rail.The guiding of the flange of the second wheel into, or out of, thesecond flange receiving passage may comprise guiding the first wheelduring the transfer between the first main rail and the first switchrail.

The wheel directing arrangement may be moveable to a first guidecondition for guiding the flange of the first wheel into, or out of, thefirst flange receiving passage as aforesaid. The wheel directingarrangement may be moveable to a second guide condition for guiding theflange of the second wheel into, or out of, the second flange receivingpassage as aforesaid.

The wheel directing arrangement may be configured to engage the wheelarrangement to maintain the first wheel in engagement with the firstmain rail as the first wheel transfers between the first main rail andthe first switch rail when the guide arrangement is in the second guidecondition. The wheel directing arrangement may be configured to engagethe wheel arrangement to maintain the second wheel in engagement withthe second main rail as the second wheel transfers between the secondmain rail and the second switch rail when the guide arrangement is inthe first guide condition.

The wheel directing arrangement may comprise a wheel control arrangementfor effecting the aforesaid control of the first and second wheels. Thewheel directing arrangement may further include a separate guidearrangement for effecting the aforesaid guiding of the first and secondwheels.

The guide arrangement may be rotationally moveable, laterally moveableand/or longitudinally moveable relative to the first main rail to guidethe flange of the first wheel as aforesaid. The guide arrangement may berotationally moveable, laterally moveable and/or longitudinally moveablerelative to the second main rail to guide the flange of the second wheelas aforesaid. Where the guide arrangement is longitudinally moveable,the guide arrangement may slide along the first and second main railsbetween the first and second guide conditions.

The wheel control arrangement may be configured to engage the wheelarrangement to maintain the first wheel in engagement with the firstmain rail as the first wheel transfers between the first main rail andthe first switch rail when the guide arrangement is in the second guidecondition. The wheel control arrangement may be configured to engage thewheel arrangement to maintain the second wheel in engagement with thesecond main rail as the second wheel transfers between the second mainrail and the second switch rail when the guide arrangement is in thefirst guide condition.

The method may further include providing a guide arrangement, guiding aflange of a first wheel of the wheel arrangement into, or out of, thefirst flange receiving passage, and guiding the flange of a second wheelof the wheel arrangement into, or out of, the second flange receivingpassage. The method may include guiding the flange of the first wheel atleast partially through the first flange receiving passage. The methodmay include guiding the flange of the second wheel at least partiallythrough the second flange receiving passage.

The guiding of the flange of the first wheel may comprise moving theguide arrangement to a first guide condition to guide the flange of thefirst wheel as aforesaid. The guiding of the flange of the second wheelmay comprise moving the guide arrangement in a second direction towardsthe second main rail to a second guide condition to guide the flange ofthe second wheel as aforesaid.

The guiding of the flange of the first wheel may comprise moving theguide arrangement in a first direction towards first main rail to thefirst guide condition. The guiding of the flange of the second wheel maycomprise moving the guide arrangement in a second direction towardssecond main rail to the second guide condition.

The maintaining of the first wheel on the first main rail duringtransfer of the first wheel between the first main rail and the firstswitch rail may comprise maintaining the first wheel on the first mainrail when the flange of the second wheel is received in the secondflange receiving passage. The maintaining of the second wheel on thesecond main rail during transfer of the second wheel between the secondmain rail and the second switch rail may comprise maintaining the secondwheel on the second main rail when the flange of the first wheel isreceived in the first flange receiving passage.

The maintaining of the first wheel on the first main rail in the firsttransition region may comprise effecting engagement of the wheel controlarrangement with the wheel arrangement, desirably with the first wheelof the wheel arrangement, when the guide arrangement is in the secondguide condition.

The maintaining of the second wheel on the second main rail in thesecond transition region may comprise effecting engagement of the wheelcontrol arrangement with the wheel arrangement when the guidearrangement is in the first guide condition. Desirably, the wheelcontrol arrangement engages the first wheel of the wheel arrangement.

The first and second main rails are desirably fixed rails. The first andsecond switch rails are desirably fixed rails.

The first and second transition regions may include respective first andsecond end regions of the first and second switch rails. In theembodiments described herein, the first and second transition regionsinclude respective regions of the first and second switch rails wherethe second wheel engages the second main rail and the second switch railwhen the guide arrangement is in the first position, and where the firstwheel engages the first main rail and the first switch rail, when theguide arrangement is in the second guide condition.

The wheel control arrangement may be configured to engage the secondwheel when the guide arrangement is in the first guide condition. Thewheel control arrangement may be configured to engage the first wheelwhen the guide arrangement is in the second guide condition.

The wheel control arrangement may have a first control surface forengaging the wheel arrangement when the guide arrangement is in thesecond guide condition, thereby maintaining the first wheel of the railvehicle on the first main rail during transfer of the first wheelbetween the first main rail and the first switch rail. The wheel controlarrangement may have a second control surface for engaging the wheelarrangement when the guide arrangement is in the first guide condition,thereby maintaining the second wheel of the rail vehicle on the secondmain rail during transfer of the second wheel between the second mainrail and the second switch rail.

The first control surface may be disposed to engage the first wheel whenthe guide arrangement is in the second guide condition. The secondcontrol surface may be disposed to engage the second wheel when theguide arrangement is in the first guide condition. The method maycomprise effecting engagement of the first control surface with thefirst wheel when the guide arrangement is in the second guide condition.The method may comprise effecting engagement of the second controlsurface with the second wheel when the guide arrangement is in the firstguide condition.

The wheel control arrangement may comprise a first wheel control memberfor engaging the first wheel, and a second wheel control member forengaging the second wheel. The first wheel control member may beprovided with the first wheel control surface, and the second wheelcontrol member may be provided with the second wheel control surface.The first and second wheel control members may be elongate and mayextend along the first and second transition regions respectively.

The wheel control arrangement may be fixed or moveable. Where the wheelcontrol arrangement is moveable, the wheel control arrangement may bemoveable to a first wheel control position to engage the wheelarrangement when the guide arrangement is in the second guide condition,and to a second wheel control position to engage the wheel arrangementwhen the guide arrangement is in the first guide condition.

Where the junction assembly is a trailing junction assembly, the wheelcontrol arrangement may be fixed. If desired, the trailing junctionassembly may be devoid of the guide arrangement.

The wheel control arrangement may be moveable to the first wheel controlposition to engage the first wheel, when the guide arrangement is in thesecond guide condition. The wheel control arrangement may be moveable tothe second wheel control position to engage the second wheel, when theguide arrangement is in the first guide condition.

The method may comprise moving the wheel control arrangement to thefirst wheel control position to engage the first wheel, when the guidearrangement is in the second guide condition. The method may comprisemoving the wheel control arrangement to the second wheel controlposition to engage the second wheel, when the guide arrangement is inthe first guide condition.

The guide arrangement may comprise a first guide member for guiding thefirst wheel into the first flange receiving passage, and a second guidemember for guiding the second wheel into the second flange receivingpassage. The first and second guide members may be elongate, and mayextend alongside the first and second main rails.

The first guide member may be configured such that, when the guidearrangement is in the first guide condition, the first guide member canengage the first wheel. The second guide member may be configured suchthat, when the guide arrangement is in the second guide condition, thesecond guide member can engage the second wheel. The method may comprisemoving the first guide member to the first position to engage the firstwheel. The method may comprise moving the second guide member to thesecond position to engage the second wheel.

In one embodiment, the wheel control arrangement may be part of theguide arrangement. In this embodiment, the first wheel control membermay constitute a portion of the first guide member, and the second wheelcontrol member may constitute a portion of the second guide member.Desirably, in this embodiment, the first wheel control member mayconstitute an end portion of the first guide member, and the secondwheel control member may constitute an end portion of the second guidemember.

In another embodiment, the first and second wheel control members may beseparate from the guide arrangement. The first wheel control member maybe moveable substantially horizontally relative to the region of thefirst switch rail in the first transition region. The second wheelcontrol member may be moveable substantially horizontally relative tothe region of the second switch rail in the second transition region.

In a further embodiment, the first and second wheel control members maybe moveable substantially vertically relative to the first transitionregion of the first switch rail. The second wheel control member may bemoveable substantially vertically relative to the second transitionregion of the second switch rail.

In the above embodiments, the first and second wheel control members maybe moveable towards and away from the respective first and secondtransition regions. When the first wheel control member is moved towardsthe first transition region, the second wheel control member is movedaway from the second transition region. When the second wheel controlmember is moved towards the second transition region, the first wheelcontrol member is moved away from the first transition region. In afourth embodiment, the first and second wheel control members may befixedly mounted adjacent the first and second transition regionsrespectively.

The wheel control arrangement may be connected to the guide arrangementso that movement of the guide arrangement effects movement of the wheelcontrol arrangement, and movement of the wheel control arrangementeffects movement of the guide arrangement.

In yet another embodiment, the first and second wheel control membersmay be fixed relative to the first and second main rails respectively.

In the embodiments described herein, the transition regions of theswitch rails are regions during use along which the rail vehicle wheelengages the switch rail and the main rail at the same time when theflange of the wheel passes along the flange receiving passage.

In the embodiments described herein, the first transition region may bea region in which the extent of engagement of the first wheel with thefirst main rail reduces, and the extent of engagement of the first wheelwith the first switch rail increases, as the first wheel moves throughthe first transition region and transfers from the first main rail tothe first switch rail.

Also in the embodiments described herein, the second transition regionmay be a region in which the extent of engagement of the second wheelwith the second main rail reduces, and the extent of engagement of thesecond wheel with the second switch rail increases, as the second wheelmoves through the second transition region and transfers from the secondmain rail to the second switch rail.

The extent of the vertical engagement of a rail vehicle wheel with arail is sometimes referred to as the bearing area. In the embodimentsdescribed herein, the aggregate bearing area on the first wheel providedby the first main rail and the first switch rail should remainsufficient so that the rail is not over stressed. The aggregate bearingarea on the first wheel provided by the first main rail and the firstswitch rail desirably remains substantially constant as the first wheeltransfers between the first main rail and the first switch rail. Also,the aggregate bearing area on the second wheel provided by the secondmain rail and the second switch rail remains substantially constant asthe second wheel transfers between the second main rail and the secondswitch rail.

It will be understood by those skilled in the art that the gauge of thefirst and second main rails widens in the first and second transitionregions.

The rail junction assembly may include a wheel urging member toselectively urge the flange of the first and second wheels along thefirst flange receiving passage or along the second flange receivingpassage.

The rail junction assembly may further include detection means to detectthe direction the rail vehicle will take or has taken. The provision ofthe detection means is particularly suitable where the junction assemblyis a trailing only junction assembly.

According to another aspect of this invention, there is provided a wheelurging member for use with a rail junction assembly as described above,the wheel urging member being configured to selectively direct theflange of the first and second wheels along the first flange receivingpassage or along the second flange receiving passage.

The wheel urging member may have a triangular top plan profile.Alternatively, the wheel urging member may have any other suitable topplan profile. In one embodiment, the wheel urging member may be wedgeshaped. In the embodiments described herein, the wedge shape of thewheel urging member provides the advantage that a single wheel urgingmember can be used selectively to direct the first wheel along the firstflange receiving passage, and to direct the second wheel along thesecond flange receiving passage.

The wheel urging member may be disposed in alignment with the firstswitch rail to direct the flange of the first wheel along the firstflange receiving passage. Alternatively, the wheel urging member may bedisposed in alignment with the second switch rail to direct the flangeof the second wheel along the second flange receiving passage.

The first switch rail may have a first wheel facing side surface whichfaces the first wheel when the flange of the first wheel passes alongthe first flange receiving passage. The wheel urging member may have afirst side surface, which is disposed in alignment with the first wheelfacing surface when the wheel urging member is disposed in alignmentwith the first switch rail.

The second switch rail may have a second wheel facing side surface whichfaces the second wheel when the flange of the second wheel passes alongthe second flange receiving passage. The wheel urging member may have asecond side surface, which is disposed in alignment with the secondwheel facing surface when the wheel urging member is disposed inalignment with the second switch rail.

The wheel urging member may comprise a main body, which may be anelongate wedge shaped main body. Alternatively, the wheel urging membermay be any other suitable shape. The wheel urging member may furtherinclude connecting means to connect the wheel urging member to a rail.The connecting means may comprise at least one connecting element. Theconnecting means may comprise a pair of connecting elements, which maybe spaced axially from each other along the length of the main body. Theconnecting elements may be attached to the lower face of the main body,and may extend downwardly therefrom.

The wheel urging member may be mounted on the rail junction assembly,and may be movable between operating and non-operating positions. Thewheel urging member may be moveable horizontally or vertically betweenthe operating and non-operating positions. The wheel urging member maybe moveable longitudinally between the operating and non-operatingpositions.

The wheel urging member may be rotatably moveable between the operatingand non-operating positions. The wheel urging member may be moveablelongitudinally between the operating and non-operating positions. Thewheel urging member may be slidable between the operating andnon-operating positions.

According to another aspect of this invention, there is provided a railswitching arrangement for switching wheels of a rail vehicle at a railjunction assembly, the rail switching arrangement comprising:

first and second wheel directing means; the first wheel directing meanscomprising a first guide member and a first wheel control member, andthe first wheel directing means being movable between a first guidingposition and a first control position, wherein in the first guidingposition, the first guide member can engage a first wheel of a wheelarrangement, and in the first control position, the first wheel controlmember can engage the first wheel;

the second wheel directing means comprising a second guide member and asecond wheel control member, and the second wheel directing means beingmovable between a second guiding position and a second control position,wherein in the second guiding position, the second guide member canengage a second wheel of the wheel arrangement, and in the secondcontrol position, the second wheel control member can engage the secondwheel; and

operating means to operable on the first and second wheel directingmeans to move the first and second wheel directing means between therespective first and second guiding positions and the first and secondcontrol positions;

wherein the first and second wheel directing means are configured sothat, when the first wheel directing means is in the first guidingposition, the second wheel directing means is in the second controlposition, and when the second wheel directing means is in the secondguiding position, the first wheel directing means is in the firstcontrol position.

The first and second wheel directing means may comprise respective firstand second rotary members. Each of the first and second rotary membersmay be elongate.

The first and second guide members may be provided on the respectivefirst and second rotary members. The first and second wheel controlmembers may be provided on the respective first and second rotarymembers.

Each of the first and second guide members may be elongate and mayextend axially along the respective first and second rotary members.Each of the first and second wheel control members may be elongate andmay extend axially along the respective first and second rotary members.

Each of the first and second rotary members may be substantiallycylindrical, and may have an elongate axially extending recess definedtherein. Each axially extending recess may be substantially V shaped.Each recess may be a cylindrical sector. Each axially extending recessmay be defined by radially extending longitudinal surfaces.

The first guide member and the first wheel control member may beprovided on the surfaces defining the recess in the first rotary member.The second guide member and the second wheel control member may beprovided on the surfaces defining the recess in the second rotarymember.

The first and second guide members may extend substantially radiallyoutwardly from the respective first and second rotary members.

The operating means may comprise first and second cranks attached to therespective first and second rotary members. The operating means maycomprise first and second push/pull members capable of applying apulling force or a pushing force to the cranks.

The operating means may include a drive arrangement for driving thefirst and second push/pull members. The drive arrangement may comprise adrive member, which may be a rotatable drive member. The first andsecond push/pull members may be attached to the drive member.

The drive arrangement may be movable between first and second operativeconditions. In the first operative condition, the first rotary member isin the first guiding position and the second rotary member is in thesecond control position. In the second operative condition, the secondrotary member is in the second guiding position and the first rotarymember is in the first control position.

When the drive arrangement moves to the first operative condition, therotatable drive member pushes the first push/pull member, which pushesthe first rotary member to the first guiding position. At the same time,the rotatable drive member pulls the second push/pull member, whichpulls the second rotary member to the second control position. When thedrive arrangement moves to the second operative condition, the rotatabledrive member pushes the second push/pull member, which pushes the secondrotary member to the second guiding position. At the same time, therotatable drive member pulls the first push/pull member, which pulls thefirst rotary member to the first control position.

Alternatively, the first and second guide members may be linearlymovable between the first and second guiding positions. The first andsecond guide members may be movable vertically or horizontally betweenthe first and second guiding positions. The first and second wheelcontrol members may be linearly movable between the first and secondcontrol positions. The first and second wheel control members may bemovable vertically or horizontally between the first and second controlpositions.

In one embodiment, the first and second guide members may define aplurality of gaps. The first and second wheel control members maycomprise a plurality of projecting portions, which can protrude throughthe gaps in the respective first and second guide members when the firstand second directing means are in the control positions.

BRIEF DESCRIPTION OF DRAWINGS

Embodiments of the invention will now be described by way of exampleonly, with reference to the accompanying drawings, in which:—

FIG. 1 is a plan view of a rail junction assembly, showing a guidearrangement in a first guide condition;

FIG. 2 is a view similar to FIG. 1 showing the guide arrangement in asecond guide condition;

FIG. 3 is an end sectional view of a rail junction assembly, with a railvehicle wheel arrangement thereon showing a guide arrangement in a firstguide condition;

FIG. 4 is an end sectional view of a rail junction assembly in which themain rails have become worn, with a rail vehicle wheel arrangementthereon showing a first wheel control arrangement;

FIG. 5 is a view similar to the views shown in FIGS. 3 and 4 but with afurther embodiment of a wheel control arrangement and a guidearrangement;

FIG. 6 is a view similar to the views shown in FIGS. 3 and 4 withanother embodiment of a wheel control arrangement and a guidearrangement;

FIG. 7 is a top plan view of a wheel urging member;

FIG. 8 is a side view of a wheel urging member;

FIG. 9 is a side view of a wheel urging member;

FIG. 10 is a top plan view of a further embodiment of a rail junctionassembly in which one of the wheel urging members shown in FIGS. 7 to 9can be used.

FIG. 11 shows an embodiment of a rail switching arrangement;

FIG. 12 is a close up of a first rotary member in a first guidingposition;

FIG. 13 is a close up of the first rotary member in a first controlposition; and

FIG. 14 shows a further embodiment of a rail junction assembly.

MODE(S) FOR CARRYING OUT THE INVENTION

FIGS. 1 and 2 show a rail junction assembly 10 which can be used fordirecting rail vehicles travelling into the rail junction assembly inthe facing direction, i.e. in the direction indicated by the arrow F inFIGS. 1 and 2 or in the trailing direction, i.e. in the directionsindicated by the arrows G and H.

The rail junction assembly 10 comprises a first fixed continuous mainrail 12, a second fixed continuous main rail 14, a first fixed switchrail 16 having an end region terminating in close proximity to the firstmain rail, and a second fixed switch rail 18 having an end regionterminating in close proximity to the second fixed main rail 14.

A first flange receiving passage 17 is defined between the first mainrail 12 and a first terminating region 16A of the first switch rail 16.A second flange receiving passage 19 is defined between the second mainrail and a second terminating region 18A of the second switch rail 18.The rail junction assembly 10 also includes a wheel directingarrangement comprising a guide arrangement 20.

The guide arrangement 20 comprises a first moveable elongate guidemember 22 and a second moveable elongate guide member 24. The first andsecond guide members 22, 24 may be laterally, longitudinally orvertically moveable. Alternatively, the first and second guide members22, 24 may be moveable in directions which have components in two ormore of the lateral, longitudinal and vertical directions.

The guide arrangement 20 is movable between first and second guideconditions. In the first guide condition, shown in FIG. 1, the firstguide member 22 is in a first guiding position shown in solid lines andthe second guide member 24 is in a first non-guiding position, shown inbroken lines. In the second guide condition, shown in FIG. 2, the firstguide member 22 is in a second non-guiding position, shown in brokenlines, and the second guide member is in a second guiding position shownin solid lines in FIG. 2.

As explained in more detail below, the first terminating region 16A ofthe first switch rail 16 is a region in which a first wheel 42 of awheel arrangement 40 engages the first main rail 12 and the first switchrail 16. Similarly, the second terminating region 18A of the secondswitch rail 16 is a region in which a second wheel 44 of the wheelarrangement 40 engages the second main rail 14 and the second switchrail 18.

The first and second wheels 42, 44 are connected to each other by arigid axle 45, whereby movement of one of the first or second wheels 42,44 is immediately transmitted to the other of the first or second wheels42, 44 so that both wheels perform the same movement. Each of the wheels42, 44 comprises a frusto-conical main portion in the form of a tread 46and an outwardly extending circumferential flange 48 on the tread 46.The flange 48 extends radially outwardly from the tread 46. Each wheel42, 44 has an inner face 50 extending across the tread 46 and the flange48.

The first elongate guide member 22 is disposed adjacent the first mainrail 12 and guides rail vehicle wheels along the first main rail 12 sothat the flanges of the rail vehicle wheels are received into the firstflange receiving passage 17. The second elongate guide member 24 isdisposed adjacent the second main rail 14 and guides rail vehicle wheelsalong the second main rail 14 so that the flanges of the rail vehiclewheels are received into the second flange receiving passage 19. Theguide arrangement 20 ensures that the wheels are guided in the desireddirection. In the embodiments described herein, the guide arrangement 20does not control the extent of lateral movement of the rail vehiclewheels on the rails.

The first and second elongate guide members 24 are fixedly attached toeach other so that when the guide arrangement 20 is moved to the firstcondition, both of the first and second elongate guide members 22, 24move together to their respective guiding and non-guiding positions.Similarly, when the guide arrangement 20 is moved to the secondcondition shown in FIG. 2, both of the first and second elongate guidemembers 22, 24 move together to their respective non-guiding and guidingpositions.

The wheel directing arrangement also includes a wheel controlarrangement 30 comprising a first elongate wheel control member 32 and asecond elongate wheel control member 34. The first wheel control member32 is disposed adjacent the first switch rail 16, and overlaps the mainrail 12 at a first transition region, which is the region comprising amain rail overlap region 12A of the first main rail 12, and the firstterminating region 16A of the first switch rail 16.

The first transition region 12A, 16A is a region from the point at whichthe flange 48 of the first wheel 42 begins to move laterally away fromthe first main rail 12 thereby allowing the tread 46 of the first wheel42 to engage the first switch rail 16. The first transition region 12A,16A terminates at, or beyond, the point at which the tread 46 of thefirst wheel 42 is fully supported by the first switch rail 16.

The second wheel control member 34 is disposed adjacent the secondswitch rail 18, and overlaps the main rail 14 at a second transitionregion, which is the region comprising a main rail overlap region 14A ofthe second main rail 14, and the second terminating region 18A of thesecond switch rail 18.

The second transition region 14A, 18A is a region from the point atwhich the flange 48 of the second wheel 44 begins to move laterally awayfrom the second main rail 14 thereby allowing the tread 46 of the secondwheel 44 to engage the second switch rail 18. The second transitionregion 14A, 18A terminates at, or beyond, the point at which the tread46 of the second wheel 44 is fully supported by the second switch rail18.

The purpose of the wheel control arrangement 30 is to ensure that therail vehicle wheels remain correctly aligned on the appropriate rails inorder to provide sufficient wheel bearing during the transition of thefirst or second wheels 42, 44 from the first main rail 12 to the firstswitch rail 16, or from the second main rail 14 to the second switchrail 18, even when the rails are worn.

The wheel control arrangement 20 stops excessive lateral movement of thewheels 42, 44 on the first and second main rails 12, 14 and on the firstand second switch rails 16, 18, thereby ensuring adequate contact areabetween the wheels and the rail or rails supporting it. It is anadvantage of the embodiments described herein that they ensuresufficient bearing of the wheel by the rail orrails to avoid damage tothe rail head or lack of support to the wheel.

The wheel control arrangement 30 is movable between first and secondwheel control conditions. In the first wheel control condition, shown inFIG. 2, the first wheel control member 32 is in a first wheel controlposition to engage the first wheel 42, thereby inhibiting excessivelateral movement of the first wheel 42 away from the first main rail 12.

In the second wheel control condition, shown in FIG. 1, the second wheelcontrol member 34 is in a second wheel control position to engage thesecond wheel 44, thereby inhibiting lateral movement of the second wheel44 away from the second main rail 14.

In use, the guide arrangement 20 can be moved in the first direction tothe first position shown in FIG. 1. A rail vehicle travelling in thedirection indicated by the arrow X in FIG. 1 along the first and secondmain rails 12, 14 is directed by the first guide member 22 so that thewheels travel along the first main rail and the second switch rail 18.Similarly, by moving the guide arrangement 20 in the second direction tothe second position shown in FIG. 2, a rail vehicle travelling in thedirection indicated by the arrow X is directed by the second guidemember 24 so that the wheels travel along the second main rail 14 andthe first switch rail 16.

FIG. 3 shows an end sectional view of the junction assembly 10 in thecondition shown in FIG. 1, i.e. with the guide arrangement 20 in thefirst position. As would be understood by the skilled person, FIG. 3shows lower portions of a known wheel arrangement 40, which comprisesfirst and second wheels 42, 44. An axle (not shown) connects the firstand second wheels 42, 44 to each other.

Lateral movement of one of the first and second wheels 42, 44 across therails causes the same lateral movement of the other wheel. The words“lateral” or “laterally” as used herein is intended to refer to movementin a substantially horizontal direction transverse to the longitudinalorientation of the rails.

In FIGS. 1 and 2, the flange 48 is represented by an oval, and the tread46 is indicated by a solid/broken line extending from the flange 48. Asolid region of the solid/broken line indicates a region of the tread 46supported by a rail. A broken region of the solid/broken line indicatesan unsupported region of the tread 46.

As shown in FIG. 3, the first guide member 22 is in its guiding positionand has an outer wheel engaging surface 52 to engage the inner face 50of the first wheel 42. The second guide member 24 has an outer wheelengaging surface 52 for engaging the inner face 50 of the second wheel44, but the second guide member 24 is in its non-guiding position, andis not shown in FIG. 3.

In FIGS. 1 and 3, the guide arrangement 20 is in the first guidecondition, with the first guide member 22 in its guiding position, andthe wheel engaging surface 52 thereof in the appropriate position toengage the inner face 50 of the first wheel 42, thereby directing thefirst wheel 42 in a direction so that the flange 48 of the first wheel42 passes into the first flange receiving passage 17.

The first wheel 42 thus continues along the first main rail 12. Thesecond wheel 44, being connected to the first wheel 42, is movedrelative to the second main rail 14 in the same lateral direction as thefirst wheel 42. Consequently, the flange 48 of the second wheel 44 ismoved away from the second main rail 14 to a position where the flange48 of the second wheel 44 engages the left hand side 18B (as shown inFIG. 3) of the second switch rail 18, thereby moving the second wheel 44onto the second switch rail 18.

Similarly, when the guide arrangement 20 is moved to the secondcondition shown in FIG. 2, the second wheel 44 is urged by the secondguide member 24 towards the second main rail 14 so that the flange 48 ofthe second wheel 44 passes into the second flange receiving passage 19.

The second wheel 44 continues along the second main rail 14, and thefirst wheel 42 is moved laterally relative to the first main rail 12towards the first guide member 22. As this occurs, the flange 48 of thefirst wheel 42 is moved away from the first main rail 12 to engage theright hand side 16B of the first switch rail 16.

In the situation shown in FIG. 1, the second wheel 44 moves away fromthe second main rail 14 to be supported by the second switch rail 18.This occurs in the second transition region 14A, 18A, and the effect ofsuch movement is that the support provided by the second main railreduces, and the support provided by the second switch rail increases.

In circumstances where the wheels and the rails are unworn and the wheeltreads are of sufficient width, having a rail vehicle wheel engage amain rail and move across to engage a switch rail should not create aproblem. This is because both wheels are supported by sufficient surfacearea of the rail head by the wheel until it passes beyond the transitionregion, at which point, the load is borne fully by the switch rail.

As the first wheel 42 moves across the first transition region 12A, 16Afrom the first main rail 12 to the first switch rail 16, the bearingarea of the first main rail 12, on the first wheel 42 decreases as thebearing area of the first switch rail 16 on the first wheel 42increases.

Similarly, as the second wheel 44 moves across the second transitionregion 14A, 18A from the second main rail 14 to the second switch rail18, the bearing area of the second main rail 14, on the second wheel 44decreases as the bearing area of the second switch rail 18 on the secondwheel 44 increases.

Thus, at all times during the movement of the first or second wheels 42,44 through the first or second transition regions, the wheel 42 or 44engages either the first or second main rails 12, 14, or the first orsecond switch rails 16, 18 or both the respective main rail 12, 14 andthe respective switch rail 16, 18.

However, where the first and second main rails 12, 14, and/or the firstand second switch rail 16, 18 and/or the wheels 42, 44 are worn and thetread 46 is insufficiently wide, insufficient support of the wheels42,44 is possible, and can present a significant risk. An example ofthis is shown in FIG. 4 in which the hatched region 58 representsregions of wear of the first main rail 12 and the first wheel 42.

Such worn regions can cause a problem if the rail vehicle wheels 42, 44drift across the rails. In such circumstances, there is a danger ofthere being insufficient contact between the first or second wheel 42,44 and the rail surfaces supporting it. This could result in significantdamage to the rail and/or derailment of the rail vehicle, the effects ofwhich could be catastrophic.

In order to prevent such a problem, the wheel control arrangement 30 isprovided. As shown in FIGS. 1 and 2 the first and second wheel controlmembers 32, 34 are provided adjacent the first and second switch railtransition regions 16A, 18A of the first and second switch rails 16, 18.The first and second wheel control members 32, 34 are disposed betweenthe first and second switch rails 16, 18

In FIG. 4, as the wheel arrangement 40 moves to the left hand side, asindicated by the arrow C, the worn region of the first main rail 12 andthe first wheel 42 creates a tendency for the wheel arrangement 40 tomove further in the lateral direction indicated by the arrow C thanwould be the case if no wearing has occurred. In such a situation,during the transfer of the second wheel 44 from the second main rail 14to the second switch rail 18, the combined wheel rail bearing areaprovided by the second rail 14 and the second switch rail 18 may beinsufficient to safely support the rail vehicle.

In order to prevent such excessive lateral movement, the second wheelcontrol member 34 engages the inner face 50 of the second wheel 44 tomaintain the tread 46 thereof on the second main rail 14, so that thesecond wheel 44 is sufficiently supported by the bearing areas betweenthe second wheel 44 and the second main rail 14 and between the secondwheel 44 and the second switch rail 18 until the second wheel 44 isfully supported on the second switch rail 18.

Correspondingly, although not shown in FIG. 4, the converse applies whenthe guide arrangement 20 is in the second guide condition and the flange48 of the second wheel 44 is received in the second flange receivingpassage 19. In this circumstance, the first wheel control member 32engages the inner face 50 of the first wheel 42 to maintain the tread 46thereof on the first main rail 12.

There is thus described above a rail junction assembly 10 that obviatesthe need for moveable switch rails, and allows rail vehicles to beswitched from one track to another while ensuring that there issufficient bearing area between the wheels and the rails throughout thetransition between the tracks. The wheels are always supported by eithera single rail or by one of the main rails 12, 14 and the correspondingswitch rail 16, 18 the rail. The rail junction assembly 10 also providesa benefit that there will be less wear of the rail head and wheel flange48.

Various modifications can be made without departing from the scope ofthe invention. For example, as shown in FIGS. 5 and 6, the wheel controlarrangement 30 can be moveable. In other embodiments, the wheeldirecting arrangement comprises first and second wheel directing means.The first wheel directing means may comprise a first guide member and afirst wheel control member as a single unit. The second wheel directingmeans may comprise a second guide member and a second wheel controlmember as a single unit.

For example, in FIG. 5, the second guide member 24 and the second wheelcontrol member 34 are shown and together form a second wheel directingmeans 60.

The second wheel directing means 60 comprises an upper wheel directingelement 62 which constitutes the second wheel control member 34. Theupper wheel directing element 62 extends upwardly from a lower wheeldirecting element 64, which constitutes the second wheel guide member24.

The lower wheel directing element 64 provides a shoulder 66 extendingfrom the upper wheel engaging element 62. The second wheel directingmeans 60 is movable between raised and lowered positions.

In the lowered position shown in solid lines in FIG. 5, the second wheelcontrol member 34 is in the second wheel control position to engage theinner face 50 of the second wheel 44. The second guide member 24 is inits non-guiding position and is below the second wheel 44, so that thesecond wheel 44 is not engaged by the second guide member 64.

In the raised position, shown in broken lines in FIG. 5 the wheeldirecting means 60 has been raised so that the second guide member 24 isin its guiding position to engage the second wheel 44 and thereby guidethe flange 48 thereof into the second flange receiving passage 19.

Although not shown in FIG. 5, a first wheel directing means is providedadjacent the first main and switch rails 12, 16. The first wheeldirecting means comprises the first guide member 22 and the first wheelcontrol member 32.

When the second wheel directing means 60 is in the lowered positionshown in solid lines in FIG. 5, the first wheel directing means is in araised position, in which the first guide member 22 can engage the firstwheel 42.

When the second wheel directing means 60 is in the raised position,shown in broken lines in FIG. 5, the first wheel directing means is in alowered position, in which the first wheel control member 32 can engagethe first wheel.

FIG. 6 shows a further example of the wheel directing arrangementcomprising first and second wheel directing means. In FIG. 6, a singlesecond wheel directing means 68 is shown. The second wheel directingmeans 68 comprises the second guide member 24 and the second wheelcontrol member 34.

The second wheel directing means is movable laterally between a itsguiding position shown in broken lines in FIG. 6, and a second wheelcontrol position shown in solid lines in FIG. 6.

In the second guiding position, the second guide member 24 is in theappropriate position to guide the flange 48 of the second wheel 44 intothe second flange receiving passage 19. In the second wheel controlposition, the second wheel control member 34 is in the appropriateposition to engage the inner face 50 of the second wheel 44 and therebycontrol the position of the second wheel 44 on the second main rail 14.

The embodiment shown in FIG. 6 also includes a first wheel directingmeans, but this is not shown in FIG. 6. The first wheel directing meanscomprises the first guide member 22 and the first wheel control member32.

The first wheel directing means is movable between a first guidingposition and a first wheel control position. In the first guidingposition, the first wheel directing means can guide the flange 48 of thefirst wheel 42 into the first flange receiving passage 17. In the wheelcontrol position, the first wheel directing means can control theposition of the first wheel 42 on the first main rail 12.

When the first wheel directing means is in the first guiding position,the second wheel directing means 68 is in the second wheel controlposition. When the first wheel directing means is in the first wheelcontrol position, the second wheel directing means 68 is in the secondguiding position.

Referring to FIGS. 7 to 10, there is shown a wheel urging member 80,which is intended for use on a rail junction assembly 110 (see FIG. 10),which is similar to the rail junction assembly 10, but is devoid of theguide arrangement 20. The rail junction assembly 110 is constructed whenrail vehicles travel only in the direction indicated by the arrow A inFIG. 10.

However, when the rail junction assembly 110 requires maintenance, itmay be necessary to drive a maintenance vehicle in the oppositedirection through the rail junction assembly 110. This can be achievedby the use of the wheel urging member 80.

The wheel urging member 80 comprises an elongate wedge shaped main body82 and a pair of connecting elements 84, 86 spaced axially from eachother along the length of the main body 82. The connecting elements 84,86 are attached to the lower face of the main body 82, and extenddownwardly therefrom.

In the embodiment shown in FIG. 8, each of the connecting elements 84,86 defines an aperture, through which a connector (not shown) can beinserted to secure the wheel urging member 80 to the rail.

The main body 82 has first and second side surfaces 90, 92, the purposeof which is explained below.

FIG. 9 shows a second embodiment of the wheel urging member 80, which isthe same as the first embodiment shown in FIGS. 7 and 8, but differs inthat the first and second connecting elements 84, 86 are in the form ofshaped tabs, which have been configured to engage correspondingformations on the rail junction assembly 110.

FIG. 10 shows a plan view of the rail junction assembly 110. In order todrive a railway vehicle through the rail junction assembly 110 in thedirection opposite to that indicated by the arrow A, the wheel urgingmember 80 is disposed in alignment either with the first switch rail 16or with the second switch rail 18, depending upon which direction oftravel is required. The wheel urging member 80 is shown in broken linesin both possible positions in FIG. 10, the broken lines indicating thatthe two positions are alternatives.

The first switch rail 16 has a flange facing side surface 116. When itis desired to direct the rail vehicle along the first main rail 12, thewheel urging member 80 is disposed at the position indicated as 80A inFIG. 10, so that the first side surface 90 thereof is aligned with thefirst flange facing surface 116 of the first switch rail 16. Thus, theflange 48 of the first wheel 42 (not shown in FIG. 10) is directed alongthe first flange receiving passage 17.

Conversely, when it is desired to direct the rail vehicle along thesecond main rail 14 the wheel urging member 80 is disposed at theposition indicated as 80B in FIG. 10, so that the second side surface 92thereof is aligned with the second flange facing surface 118 of thesecond switch rail 18. Thus, the flange 48 of the second wheel 44 (notshown in FIG. 10) is directed along the second flange receiving passage19.

FIGS. 11 to 13 show a rail switching arrangement 210 for use in the railjunction assembly 10 described above. The rail switching arrangement 210comprises a first directing means 212 comprising a first elongatecylindrical rotary member 214, mounted on supports 216, and held on thesupports 216 by C shaped holders 218. The rail switching arrangement 210further includes a second directing means 220 comprising a secondelongate cylindrical rotary member 222.

The second elongate cylindrical rotary member 222 is also held on thesupports 216 by C shaped members, but these are not visible in FIG. 11.

The rail switching arrangement 210 is mounted between first and secondmain rails 224 (see FIGS. 12 and 13, in which only the first main rail224 is shown) in the form of embedded rails. The first rotary member 214extends alongside the first main rail 224. The second rotary member 222extends alongside the second main rail.

The first main rail 224 and the second main rail are mounted withinrespective elongate rail holding arrangements 226. In FIG. 11, the firstand second main rails are not shown, only the rail holding arrangements226. Each of the rail holding arrangements 226 comprise a pair ofopposed rail holding members 228 between which the first and second mainrails 224 are mounted.

The first and second rotary members 214, 222 are rotatable about theirmain axes between respective first and second guiding positions andrespective first and second control positions.

The first and second rotary members 214, 222 are connected to each otherby an operating means 230, which comprises a first elongate push/pullmember 232 in the form of a first rod and a second elongate push/pullmember 234 in the form of a second rod.

One end of the first push/pull member 232 is connected to the firstrotary member 214 by a first crank 236, and one end of the secondpush/pull member 234 is connected to the second rotary member 222 by asecond crank (not visible in the drawings),

At their opposite ends, the first and second push/pull members 232, 234are connected to a shaft 238 via a central crank 240. A drive means 242is drivingly connected to the shaft 238. The drive means 242 maycomprise a motor which can rotate the shaft 238 about its main axis.

When the shaft 238 is rotated by the drive means 242 in the directionindicated by the arrow R in FIG. 11, the first and second push/pullmembers 232, 234 are moved to cause the first and second rotary members214, 222 to rotate in the same direction. This moves the first rotarymember 214 from its first guiding position to its first controlposition, and also moves the second rotary member 222 from its secondcontrol position to its second guiding position.

When the shaft 238 is rotated by the drive means 242 in the oppositedirection to that indicated by the arrow R in FIG. 11, the first andsecond rotary members 214, 222 are rotated correspondingly by themovement of the push/pull members 232, 234. The first rotary member 214is moved from its first control position to its first guiding position,and the second rotary member 222 is moved from its second guidingposition to its second control position.

Referring to FIGS. 12 and 13, there is shown a close up end view of thefirst rotary member 214. FIG. 12 shows the first rotary member 214 inthe first guiding position, and FIG. 13 shows the first rotary member inthe first control position. As can be seen from FIGS. 12 and 13, thefirst rotary member 214 defines a first elongate V shaped recess 250,which extends the length of the first rotary member 214, and has upperand lower surfaces 252, 254.

FIGS. 12 and 13 also show a first wheel 264 of a wheel arrangement. Asecond wheel of the wheel arrangement travels along the second mainrail.

A first guide member 256 is mounted on the first rotary member 214 onthe lower surface 254 of the first V shaped recess 250. The first guidemember 252 extends from the recess 250 radially outwardly beyond thefirst rotary member 214.

A first wheel control member 258 is mounted on the first rotary member214 on the upper surface 254, and has an outer surface coplanar with theupper surface 254 of the first V shaped recess 250.

It will be appreciated that the second rotary member 222 has a secondelongate V shaped recess, which is substantially the same as the firstelongate V shaped recess. A second guide member and a second controlmember are provided on the second rotary member 222.

FIG. 12 shows in broken lines a first switch rail 260, and a firstflange receiving passage 262 is defined between the first main rail 224and the first switch rail 260. In FIG. 12, the first main rail 224 andthe first switch rail 260 are shown as rectangular embedded rails, butthey could be, for example, flat bottom rails and they may be, forexample, surface mounted. The first rotary member 214 is in the firstguiding position, in which the first guide member 256 engages the firstwheel 264 thereby urging the first wheel 264 into the first flangereceiving passage 262.

When the first rotary member 214 is moved to the first guiding position,by movement of the first push/pull member 232 in the direction as shownby the arrow S in FIG. 12, the second rotary member 222 is moved to thesecond control position. In the second control position, the secondcontrol member engages the second wheel to control the second wheel onthe second main rail.

When the first rotary member 214 is moved to the first control position,by movement of the first push/pull member 232 in the direction indicatedby the arrow T in FIG. 13, the second rotary member is moved to thesecond guiding position. In the second guiding position, the secondguide member engages the second wheel to urge the second wheel into asecond flange receiving passage.

This has the effect moving the first wheel 264 in the directionindicated by the arrow U to the position of the first wheel 264 shown inFIG. 13, in which the support on the first wheel 264 from the first mainrail 224 is reduced. The first control member 258 engages the wheel 264,thereby preventing further movement of the first wheel 264 in thedirection indicated by the arrow U.

In a further modification, the first and second guide members may eachdefine a plurality of gaps. The first and second control members maycomprise a plurality of projecting portions, which can protrude throughthe gaps in the respective first and second guide members when the firstand second guide members are arranged in their non-guiding positions.

The embodiment of the rail junction assembly 10 shown in FIGS. 1 and 2,and described above, includes the guide arrangement 20 to guide railvehicles travelling in the directions indicated by the arrows X and Y.Rail vehicles can also travel through the rail junction assembly 10 inthe directions opposite to the directions indicated by the arrows X andY.

FIG. 14 shows a further embodiment of a rail junction, generallydesignated 210, which is intended to be used only by rail vehiclestravelling in the trailing directions indicated by the arrows S and T.The rail junction assembly 210 includes many of the features of the railjunction 10, and these features have been designated with the samereference numerals, and function in the same way as the correspondingfeatures shown in FIGS. 1 and 2.

The junction assembly 210 differs from the junction assembly 10 in thatthe junction assembly 210 does not possess a guide arrangement. Thejunction assembly also possesses a fixed wheel control arrangementgenerally designated 230. The wheel control arrangement 230 comprises afixed first control member 232 and a fixed second control member 234 hepurpose of the wheel control arrangement 230.

The first control member 232 is provided to control the position of thefirst wheels 42 as the wheel arrangements 40 travel in the direction ofthe arrow T and the first wheels 42 travel from the first switch rail 16to the first main rail 12. The first control member 232 ensures thatthere is sufficient bearing area between the first wheels 42 and thefirst switch and main rails 16, 12 throughout the transfer of the firstwheels 42 between the first switch rail 16 and the first main rail 12.

The first wheels 42 are thus sufficiently supported by the bearing areasbetween the first wheels 42 and the first main rail 12 and between thefirst wheels 42 and the first switch rail 16 until the first wheels 42is fully supported on the first main rail 16.

The second control member 234 is provided to control the position of thesecond wheels 44 as the wheel arrangements 40 travel from the secondswitch rail 18 to the second main rail 14, thereby ensuring the secondwheels 44 are sufficiently supported throughout the transfer of thesecond wheels 44 from the second switch rail 18 to the second main rail14.

1. A rail junction assembly for directing first and second rail vehiclewheels of a wheel arrangement, the first and second wheels havingrespective first and second flanges, the rail junction assemblycomprising: first and second main rails; first and second switch rails;a first flange receiving passage being defined between the first switchrail and the first main rail, and a second flange receiving passagebeing defined between the second switch rail and the second main rail;wherein the first flange receiving passage is configured to receive thefirst flange of the first wheel, and the second wheel can transferbetween the second main rail and the second switch rail when the firstflange is received in the first flange receiving passage, and whereinthe second flange receiving passage is configured to receive the secondflange of the second wheel, and the first wheel can transfer between thefirst main rail and the first switch rail when the second flange isreceived in the second flange receiving passage; and wheel directingarrangement for controlling the first wheel on the first main rail andon the first switch rail when the second flange is received in thesecond flange receiving passage, and for controlling the second wheel onwith the second main rail and on the second switch rail when the firstflange is received in the first flange receiving passage.
 2. A railjunction assembly according to claim 1, wherein the first and secondmain rails are fixed rails, and the first and second switch rails arefixed rails.
 3. A rail junction assembly according to claim 1 or 2,wherein the first switch rail has a first terminating region adjacentthe first main rail, the first switch rail and the first main raildefining a first transition region, and wherein the second switch railhas a second terminating region adjacent the second main rail, thesecond switch rail and the second main rail defining a second transitionregion.
 4. A rail junction assembly according to claim 3, wherein thefirst transition region comprises a region of the first main rail and aregion extending from the point at which, in use, the first rail vehiclewheel begins to move laterally away from the first main rail to besupported by the first switch rail, the first transition regionterminating at a point at which, in use, the rail vehicle wheel is fullysupported by the first switch rail.
 5. A rail junction assemblyaccording to claim 3 or 4, wherein the second transition regioncomprises a region of the second main rail and a region extending fromthe point at which, in use, the second rail vehicle wheel begins to movelaterally away from the second main rail to be supported by the secondswitch rail, the second transition region terminating at a point atwhich, in use, the rail vehicle wheel is fully supported by the secondswitch rail.
 6. A rail junction assembly according to any precedingclaim, wherein the wheel directing arrangement is configured to controlthe first wheel during said transfer of the first wheel.
 7. A railjunction assembly according to any preceding claim, wherein the wheeldirecting arrangement is configured to control the second wheel duringsaid transfer of the second wheel.
 8. A rail junction assembly accordingto any preceding claim, wherein the wheel directing arrangementcomprises a guide arrangement for guiding the first flange of a firstwheel into, or out of, the first flange receiving passage, and forguiding the second flange of the second wheel into, or out of, thesecond flange receiving passage, the guide arrangement being moveable toa first guide condition for guiding the first flange into, or out of,the first flange receiving passage, and the guide arrangement ismoveable to a second guide condition for guiding the second flange into,or out of, the second flange receiving passage.
 9. A rail junctionassembly according to claim 8, wherein the wheel directing arrangementcomprises a wheel control arrangement for effecting the aforesaidcontrol of the first and second wheels.
 10. A rail junction assemblyaccording to claim 9, wherein the wheel control arrangement isconfigured to engage the wheel arrangement when the guide arrangement isin the second guide condition to maintain the first wheel in engagementwith the first main rail when the first wheel transfers between thefirst main rail and the first switch rail.
 11. A rail junction assemblyaccording to claim 9 or 10, wherein the wheel control arrangement isconfigured to engage the wheel arrangement when the guide arrangement isin the first guide condition to maintain the second wheel in engagementwith the second main rail when the second wheel transfers between thesecond main rail and the second switch rail.
 12. A rail junctionassembly according to claim 9, 10 or 11, wherein the wheel controlarrangement is configured to engage the second wheel when the guidearrangement is in the first guide condition, and the wheel arrangementis configured to engage the first wheel when the guide arrangement is inthe second guide condition.
 13. A rail junction assembly according toany of claims 9 to 12, wherein the wheel control arrangement has a firstcontrol surface for engaging the wheel arrangement when the guidearrangement is in the second guide condition, thereby maintaining thefirst rail vehicle wheel on the first main rail when the first wheeltransfers between the first main rail and the first switch rail, and thewheel control arrangement has a second control surface for engaging thewheel arrangement when the guide arrangement is in the first guidecondition, thereby maintaining the second rail vehicle wheel on thesecond main rail when the second wheel transfers between the second mainrail and the second switch rail.
 14. A rail junction assembly accordingto claim 13, wherein the first control surface is disposed to engage thefirst wheel when the guide arrangement is in the second guide condition,and the second control surface is disposed to engage the second wheelwhen the guide arrangement is in the first guide condition.
 15. A railjunction assembly according to claim 13 or 14, wherein the wheel controlarrangement comprises a first wheel control member for engaging thefirst wheel, and a second wheel control member for engaging the secondwheel, the first wheel control member being provided with the firstwheel control surface, and the second wheel control member beingprovided with the second wheel control surface.
 16. A rail junctionassembly according to claim 15, wherein the wheel control arrangement ispart of the guide arrangement, the first wheel control memberconstituting a portion of the first guide member, and the second wheelcontrol member constituting a portion of the second guide member.
 17. Arail junction assembly according to claim 15, wherein the first wheelcontrol member constitutes an end portion of the first guide member, andthe second wheel control member constitutes an end portion of the secondguide member.
 18. A rail junction assembly according to claim 15,wherein the first and second wheel control members are separate from theguide arrangement, the first wheel control member being moveablesubstantially horizontally relative to the first switch rail, and thesecond wheel control member being moveable substantially horizontallyrelative to the second switch rail.
 19. A rail junction assemblyaccording to claim 15, wherein the first and second wheel controlmembers are separate from the guide arrangement, the first wheel controlmember being moveable substantially vertically relative to the firstswitch rail, and the second wheel control member being moveablesubstantially vertically relative to the second switch rail.
 20. A railjunction assembly according to any of claims 15 to 19, wherein the firstand second wheel control members are moveable towards and away from therespective first and second switch rails, whereby when the first wheelcontrol member is moved towards the first switch rail, the second wheelcontrol member is moved away from the second switch rail, and when thesecond wheel control member is moved towards the second switch rail, thefirst wheel control member is moved away from the first switch rail. 21.A rail junction assembly according to any of claims 9 to 19, wherein thewheel control arrangement is moveable to a first wheel control positionto engage the wheel arrangement when the guide arrangement is in thesecond guide condition, and to a second wheel control position to engagethe wheel arrangement when the guide arrangement is in the first guidecondition.
 22. A rail junction assembly according to claim 21, whereinthe wheel control arrangement is moveable to the first wheel controlposition to engage the first wheel, when the guide arrangement is in thesecond guide condition, and the wheel control arrangement is moveable tothe second wheel control position to engage the second wheel, when theguide arrangement is in the first guide condition.
 23. A rail junctionassembly according to any of claims 9 to 21, wherein the guidearrangement comprises a first guide member for guiding the first wheelinto the first flange receiving passage, and a second guide member forguiding the second wheel into the second flange receiving passage.
 24. Arail junction assembly according to claim 23, wherein the first andsecond guide members are elongate and extend alongside the respectivefirst and second main rails.
 25. A rail junction assembly according toclaim 23 or 24, wherein the first guide member is configured so that,when the guide arrangement is in the first guide condition, the firstguide member can engage the first wheel, and the second guide member isconfigured so that, when the guide arrangement is in the second guidecondition, the second guide member can engage the second wheel.
 26. Arail junction assembly according to any preceding claim, wherein therail junction assembly includes a wheel urging member to selectivelydirect either the flange of the first wheel along the first flangereceiving passage or the flange of the second wheel along the secondflange receiving passage.
 27. A rail junction assembly according toclaim 26, wherein the rail wheel urging member has a triangular top planprofile.
 28. A rail junction assembly according to claim 26 or 27,wherein the rail wheel urging member is wedge shaped.
 29. A railjunction assembly according to claim 26, 27 or 28 wherein the rail wheelurging member is disposed in alignment with the first switch rail todirect the flange of the first wheel along the first flange receivingpassage.
 30. A rail junction assembly according to claim 26, 27 or 28wherein the rail wheel urging member is disposed in alignment with thesecond switch rail to direct the flange of the second wheel along thesecond flange receiving passage.
 31. A rail junction assembly accordingto any of claims 26 to 30, wherein the first switch rail has a firstwheel facing side surface which faces the first wheel when the flange ofthe first wheel passes along the first flange receiving passage, andwherein the rail wheel urging member has a first side surface, which isdisposed in alignment with the first wheel facing surface when the railwheel urging member is disposed in alignment with the first switch rail.32. A rail junction assembly according to any of claims 26 to 31,wherein the second switch rail has a second wheel facing side surfacewhich faces the second wheel when the flange of the second wheel passesalong the second flange receiving passage, and wherein the rail wheelurging member has a second side surface, which is disposed in alignmentwith the second wheel facing surface when the rail wheel urging memberis disposed in alignment with the second switch rail.
 33. A railjunction assembly according to any of claims 26 to 32, wherein the railwheel urging member comprises an elongate wedge shaped main body, andincludes connecting means on the main body to connect the rail wheelurging member to a rail.
 34. A rail junction assembly according to claim33, wherein the connecting means comprises a pair of connecting elementsspaced axially from each other along the length of the main body, theconnecting elements may be attached to the lower face of the main body,and extending downwardly therefrom.
 35. A method of directing a firstand second rail vehicle wheels of a wheel arrangement, the first andsecond wheels having respective first and second flanges, the methodcomprising: providing first and second main rails, and first and secondswitch rails, the first switch rail being spaced from the first mainrails to define a first flange receiving passage therebetween, and thesecond switch rail being spaced from the second main rail to define asecond flange receiving passage therebetween; wherein the first flangereceiving passage is configured to receive the first flange of the firstwheel, and the second wheel can transfer between the second main railand the second switch rail when the first flange is received in thefirst flange receiving passage, and wherein the second flange receivingpassage is configured to receive the second flange of the second wheel,and the first wheel can transfer between the first main rail and thefirst switch rail when the second flange is received in the secondflange receiving passage; providing a wheel directing arrangement, and,with the wheel directing arrangement, controlling the first wheel on thefirst main rail when the second flange is received in the second flangereceiving passage, and controlling the second wheel on the second mainrail when the first flange is received in the first flange receivingpassage.
 36. A method according to claim 35, wherein the first switchrail has a first terminating region adjacent the first main rail, thefirst switch rail and the first main rail defining a first transitionregion, and wherein the second switch rail has a second terminatingregion adjacent the second main rail, the second switch rail and thesecond main rail defining a second transition region.
 37. A methodaccording to claim 36, wherein the first transition region comprises aregion of the first main rail and a region extending from the point atwhich, in use, the first rail vehicle wheel begins to move laterallyaway from the first main rail to be supported by the first switch rail,the first transition region terminating at a point at which, in use, therail vehicle wheel is fully supported by the first switch rail.
 38. Amethod according to claim 37, wherein the second transition regioncomprises a region of the second main rail and a region extending fromthe point at which, in use, the second rail vehicle wheel begins to movelaterally away from the second main rail to be supported by the secondswitch rail, the second transition region terminating at a point atwhich, in use, the rail vehicle wheel is fully supported by the secondswitch rail.
 39. A rail junction assembly according to any of claims 35to 38, wherein the controlling of the first wheel on the first main railand on the first switch rail comprises controlling the first wheelduring said transfer of the first wheel between the first main rail andthe first switch rail.
 40. A rail junction assembly according to any ofclaims 35 to 39, wherein the controlling of the second wheel on thesecond main rail and on the second switch rail comprises controlling thesecond wheel during said transfer of the second wheel between the secondmain rail and the second switch rail.
 41. A method according to any ofclaims 35 to 40, wherein the wheel directing arrangement comprises aguide arrangement, and the method includes guiding a flange of a firstwheel of the wheel arrangement into, or out of, the first flangereceiving passage,
 42. A method according to any of claims 35 to 41,further including guiding the flange of a second wheel of the wheelarrangement into, or out of, the second flange receiving passage.
 43. Amethod according to claim 41, wherein the guiding of the flange of thefirst wheel comprises moving the guide arrangement in a first directiontowards the first main rail to a first guide condition to guide theflange of the first wheel as aforesaid,
 44. A method according to claim43, wherein the guiding of the flange of the second wheel comprisesmoving the guide arrangement in a second direction towards the secondmain rail to a second guide condition to guide the flange of the secondwheel as aforesaid.
 45. A method according to any of claims 41 to 44,wherein the controlling of the first wheel on the first main rail duringsaid transfer of the first wheel between the first main rail and thefirst switch rail comprises maintaining the first wheel in engagementwith the first main rail when the flange of the second wheel is receivedin the second flange receiving passage.
 46. A method according to any ofclaims 41 to 45, wherein the controlling of the second wheel on thesecond main rail during said transfer of the second wheel between thesecond main rail and the second switch rail comprises maintaining thesecond wheel on the second main rail when the flange of the first wheelis received in the first flange receiving passage.
 47. A methodaccording to claim 45, wherein the wheel directing arrangement comprisesa wheel control arrangement, and the maintaining of the first wheel inengagement with the first main rail in the during said transfer of thefirst wheel between the first main rail and the first switch railcomprises effecting engagement of the wheel control arrangement with thewheel arrangement, when the guide arrangement is in the second guidecondition.
 48. A method according to claim 46, wherein the maintainingof the second wheel in engagement with the second main rail during saidtransfer of the second wheel between the second main rail and the secondswitch rail comprises effecting engagement of the wheel controlarrangement with the wheel arrangement when the guide arrangement is inthe first guide condition.
 49. A method according to claim 47 or 48,wherein the wheel control arrangement has a first control surface forengaging the wheel arrangement when the guide arrangement is in thesecond guide condition, thereby maintaining the first rail vehicle wheelin engagement with the first main rail in during said transfer of thefirst wheel between the first main rail and the first switch rail, andthe method comprises effecting engagement of the first control surfacewith the first wheel when the guide arrangement is in the second guidecondition.
 50. A method according to claim 47, 48 or 49, wherein thewheel control arrangement has a second control surface for engaging thewheel arrangement when the guide arrangement is in the first guidecondition, thereby maintaining the second rail vehicle wheel inengagement with the second main rail during said transfer of the secondwheel between the second main rail and the second switch rail, and themethod comprises effecting engagement of the second control surface withthe second rail vehicle wheel when the guide arrangement is in the firstguide condition.
 51. A method according to any of claims 47 to 50,comprising moving the wheel control arrangement to a first wheel controlposition to engage the wheel arrangement when the guide arrangement isin the second guide condition,
 52. A method according to claim 51,comprising moving the wheel control arrangement to the first wheelcontrol position to engage the first wheel, when the guide arrangementis in the second guide condition.
 53. A method according to claim 51 or52, comprising moving the wheel control arrangement to a second wheelcontrol position to engage the wheel arrangement when the guidearrangement is in the first guide condition.
 54. A method according toclaim 53, comprising moving the wheel control arrangement to the secondwheel control position to engage the second wheel, when the guidearrangement is in the first guide condition.
 55. A method according toany of claims 47 to 54, wherein the guide arrangement comprises a firstguide member for guiding the first wheel into the first flange receivingpassage, and a second guide member for guiding the second wheel into thesecond flange receiving passage.
 56. A method according to claim 55,wherein the first guide member is configured so that, when the guidearrangement is in the first guide condition, the first guide member canengage the first wheel, and the method comprises moving the first guidemember to the first position to engage the first wheel.
 57. A methodaccording to claim 55 or 56, wherein the second guide member isconfigured so that, when the guide arrangement is in the second guidecondition, the second guide member can engage the second wheel, and themethod comprises moving the second guide member to the second positionto engage the second wheel.
 58. A method according to any of claims 47to 56, wherein the wheel control arrangement comprises first and secondwheel control members
 59. A method according to claim 58, includingmoving the first wheel control member substantially horizontallyrelative to the first transition region of the first switch rail, andmoving the second wheel control member substantially horizontallyrelative to the second transition region of the second switch rail. 60.A method according to claim 59, including moving the first wheel controlmembers substantially vertically relative to the first transition regionof the first switch rail, and moving the second wheel control membersubstantially vertically relative to the second transition region of thesecond switch rail.
 61. A method according to claim 58, 59 or 60,including moving the first and second wheel control members towards andaway from the respective first and second switch rails.
 62. A methodaccording to claim 61, including moving the first wheel control membertowards the first transition region, thereby moving the second wheelcontrol member away from the second switch rail.
 63. A method accordingto claim 61, including moving the second wheel control member towardsthe second transition region, thereby moving the first wheel controlmember away from the first switch rail.
 64. A method according to any ofclaims 35 to 63, including providing a rail wheel urging member toselectively urge the flange of the first and second wheels along thefirst flange receiving passage or along the second flange receivingpassage.
 65. A method according to claim 64, including disposing therail wheel urging member in alignment with the first switch rail todirect the flange of the first wheel along the first flange receivingpassage.
 66. A method according to claim 64, including disposing therail wheel urging member in alignment with the second switch rail todirect the flange of the second wheel along the second flange receivingpassage.
 67. A method according to claim 64, 65 or 66, wherein the firstswitch rail has a first wheel facing side surface which faces the firstwheel when the flange of the first wheel passes along the first flangereceiving passage, and wherein the rail wheel urging member has a firstside surface, and the method comprises disposing the first side surfaceof the rail wheel urging member in alignment with the first wheel facingsurface when the rail wheel urging member is disposed in alignment withthe first switch rail.
 68. A method according to claim 64, 65 or 66,wherein the second switch rail has a second wheel facing side surfacewhich faces the second wheel when the flange of the second wheel passesalong the second flange receiving passage, and wherein the rail wheelurging member has a second side surface, and the method comprisesdisposing the second side surface in alignment with the second wheelfacing surface when the rail wheel urging member is disposed inalignment with the second switch rail.
 69. A method according to any ofclaims 35 to 68, wherein the rail wheel urging member comprises a mainbody and connecting means on the main body to connect the rail wheelurging member to a rail, and the method comprises connecting the railwheel urging member to the rail using the connecting means.
 70. A railwheel urging member for use with a rail junction assembly as claimed inclaim 1, the rail wheel urging member being configured to be selectivelymounted either between the first main rail and the first switch rail todirect the flange of the first wheel to transfer between the first mainrail and the first switch rail, or between the second main rail and thesecond switch rail to direct the flange of the second wheel to transferbetween the second main rail and the second switch rail.
 71. A railwheel urging member according to claim 70, being configured to extendbetween the first main rail and the first switch rail, or between thesecond main rail and the second switch rail and to engage first orsecond wheel and thereby urge the first or second wheel to transferbetween first main rail and the first switch rail, or between the secondmain rail and the second switch rail.
 72. A rail wheel urging memberaccording to claim 70 or 71, having a triangular top plan profile.
 73. Arail wheel urging member according to claim 70, 71 or 72 being wedgeshaped.
 74. A rail wheel urging member according to any of claims 70 to73 having a first side surface, which can be disposed in alignment witha first wheel facing surface of a first switch rail when the rail wheelurging member is disposed in alignment with the first switch rail.
 75. Arail wheel urging member according to claim 74, having a second sidesurface, which is disposed in alignment with the second wheel facingsurface of a second switch rail when the rail wheel urging member isdisposed in alignment with the second switch rail.
 76. A rail wheelurging member according to any of claims 70 to 75, comprising anelongate wedge shaped main body, and includes connecting means on themain body to connect the rail wheel urging member to a rail.
 77. A railwheel urging member according to claim 76, wherein the connecting meanscomprises a pair of connecting elements spaced axially from each otheralong the length of the main body, the connecting elements may beattached to the lower face of the main body, and extending downwardlytherefrom.
 78. The use of a rail wheel urging member with a railjunction assembly as claimed in claim 1, comprising disposing the railwheel urging member between the first main rail and the first switchrail to direct the flange of the second wheel along the second flangereceiving passage, or between the second main rail and the second switchrail to direct the flange of the first wheel along the first flangereceiving passage, wherein the rail wheel urging member is configured tourge the first or second wheel to transfer between the first main railand the first switch rail.
 79. The use according to claim 78 comprisingarranging the rail wheel urging member to extend between the first mainrail and the first switch rail in engagement with the first main railand the first switch rail, or between the second main rail and thesecond switch rail in engagement with the second main rail and thesecond switch rail, and to engage first or second wheel and thereby urgethe first or second wheel to transfer between first main rail and thefirst switch rail, or between the second main rail and the second switchrail.
 80. The use according to claim 78 or 79, wherein the rail wheelurging member has a triangular top plan profile.
 81. The use accordingto claim 78, 79 or 80, wherein the rail wheel urging member is wedgeshaped.
 82. The use according to any of claims 78 to 81, wherein therail wheel urging member has a first side surface, which can be disposedin alignment with a first wheel facing surface of a first switch railwhen the rail wheel urging member is disposed in alignment with thefirst switch rail.
 83. The use according to any of claims 78 to 82,wherein the rail wheel urging member has a second side surface, which isdisposed in alignment with the second wheel facing surface of a secondswitch rail when the rail wheel urging member is disposed in alignmentwith the second switch rail.
 84. The use according to any of claims 78to 83, wherein the rail wheel urging member has an elongate wedge shapedmain body, and includes connecting means on the main body to connect therail wheel urging member to a rail.
 85. The use according to claim 84,wherein the connecting means comprises a pair of connecting elementsspaced axially from each other along the length of the main body, theconnecting elements may be attached to the lower face of the main body,and extending downwardly therefrom.
 86. A rail switching arrangement forswitching rail vehicle wheels at a rail junction assembly, the railswitching arrangement comprising: first and second wheel directingmeans; the first wheel directing means comprising a first guide memberand a first control member, and the first wheel directing means beingmovable between a first guiding position and a first control position,wherein in the first guiding position, the first guide member can engagea first wheel of a wheel arrangement, and in the first control position,the first control member can engage the first wheel; the second wheeldirecting means comprising a second guide member and a second controlmember, and the second wheel directing means being movable between asecond guiding position and a second control position, wherein in thesecond guiding position, the second guide member can engage a secondwheel of the wheel arrangement, and in the second control position, thesecond control member can engage the second wheel; and operating meansto operable on the first and second wheel directing means to move thefirst and second wheel directing means between the respective first andsecond guiding positions and the first and second control positions;wherein the first and second wheel directing means are configured sothat, when the first wheel directing means is in the first guidingposition, the second wheel directing means is in the second controlposition, and when the second wheel directing means is in the secondguiding position, the first wheel directing means is in the firstcontrol position.
 87. A rail switching arrangement according to claim86, wherein the first and second wheel directing means compriserespective first and second rotary members.
 88. A rail switchingarrangement according to claim 85, wherein each of the first and secondrotary members is elongate.
 89. A rail switching arrangement accordingto claim 87 or 88, wherein the first and second guide members areprovided on the respective first and second rotary members, and whereinthe first and second control members are provided on the respectivefirst and second rotary members.
 90. A rail switching arrangementaccording to any of claims 87 to 89, wherein each of the first andsecond guide members is elongate and extends axially along therespective first and second rotary members, and wherein each of thefirst and second control members is elongate and extends axially alongthe respective first and second rotary members.
 91. A rail switchingarrangement according to any of claims 87 to 90, wherein each of thefirst and second rotary members is substantially cylindrical, and has anelongate axially extending recess defined therein.
 92. A rail switchingarrangement according to claim 91, wherein each axially extending recessis substantially V shaped, each axially extending recess being definedby radially extending longitudinal surfaces.
 93. A rail switchingarrangement according to claim 91 or 92, wherein the first guide memberand the first control member are provided on the surfaces defining therecess in the first rotary member and wherein the second guide memberand the second control member are provided on the surfaces defining therecess in the second rotary member.
 94. A rail switching arrangementaccording to claim 3 wherein the first and second guide members mayextend substantially radially outwardly from the respective first andsecond rotary members.
 95. A rail switching arrangement according to anyof claims 87 to 94, wherein the operating means comprises first andsecond cranks attached to the respective first and second rotarymembers, the operating means comprising first and second push/pullmembers capable of applying a pulling force or a pushing force to thecranks.
 96. A rail switching arrangement according to claim 95, whereinthe operating means further includes a drive arrangement for driving thefirst and second push/pull members.
 97. A rail switching arrangementaccording to claim 96, wherein the drive arrangement comprises arotatable drive member, and wherein the first and second push/pullmembers are attached to the drive member.
 98. A rail switchingarrangement according to claim 97 or 97, wherein the drive arrangementis movable between first and second operative conditions, whereby in thefirst operative condition, the first rotary member is in the firstguiding position and the second rotary member is in the second controlposition and in the second operative condition, the second rotary memberis in the second guiding position and the first rotary member is in thefirst control position.
 99. A rail switching arrangement according toclaim 98, wherein when the drive arrangement moves to the firstoperative condition, the rotatable drive member pushes the firstpush/pull member, which pushes the first rotary member to the firstguiding position, and the rotatable drive member pulls the secondpush/pull member, which pulls the second rotary member to the secondcontrol position.
 100. A rail switching arrangement according to claim99, wherein when the drive arrangement moves to the second operativecondition, the rotatable drive member pushes the second push/pullmember, which pushes the second rotary member to the second guidingposition, and the rotatable drive member pulls the first push/pullmember, which pulls the first rotary member to the first controlposition.
 101. A rail switching arrangement according to claim 86,wherein the first and second guide members are linearly movable betweenthe first and second guiding positions, and the first and second controlmembers are linearly movable between the first and second controlpositions.
 102. A rail switching arrangement according to claim 101,wherein the first and second guide members are movable vertically orhorizontally between the first and second guiding positions, and thefirst and second control members are movable vertically or horizontallybetween the first and second control positions.
 103. A rail switchingarrangement according to any of claims 96 to 102, wherein the first andsecond guide members define a plurality of gaps, and the first andsecond control members comprise a plurality of projecting portions,which can protrude through the gaps in the respective first and secondguide members when the first and second directing means are in thecontrol positions.